Submitted on: 22 May 1998.
Revised on: 02 June 1998.
Accepted on: 09 June 1998.
Novos Cadernos NAEA---UNIV FEDERAL PARA
http://reply.papertrans.cn/3/233/23293/23293-12.png
Submitted on: 28 January 2010.
Revised on: 09 March 2010.
Accepted on: 26 March 2010.
Novos Cadernos NAEA---UNIV FEDERAL PARA
Submitted on: 12 March 2018.
Revised on: 13 April 2018.
Accepted on: 21 April 2018.
Novos Cadernos NAEA---UNIV FEDERAL PARA
Submitted on: 15 September 2000.
Revised on: 27 September 2000.
Accepted on: 07 October 2000.
Novos Cadernos NAEA
Submitted on: 03 June 2014.
Revised on: 25 June 2014.
Accepted on: 22 July 2014.
Novos Cadernos NAEA---UNIV FEDERAL PARA
Submitted on: 19 December 2017.
Revised on: 22 January 2018.
Accepted on: 28 January 2018.
Novos Cadernos NAEA
http://reply.papertrans.cn/3/233/23293/23293-18.png
Submitted on: 12 September 2006.
Revised on: 25 October 2006.
Accepted on: 15 November 2006.
Novos Cadernos NAEA---UNIV FEDERAL PARA
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